Characteristics and advantages of tinplate

1. Impermeability

　　In addition to the deterioration of food, light also causes changes in proteins and amino acids. When Vitamin C is exposed to light, it is easier for it to interact with other food ingredients, resulting in a large amount of loss. According to research and analysis, transparent glass bottles of milk, vitamin C loss than the dark bottle of milk 14 times higher, the light will also make the milk produce oxidation odor, as well as nuclides, methyl thiamine acid and other cleavage and loss of nutritional value, tinplate cans impermeable to make the highest preservation of vitamin C rate.

2. Good sealing

Packaging containers to air and other volatile gases barrier to the preservation of nutrients and sensory quality is very important. Comparison of various fruit juice packaging containers proved that the oxygen transmission rate of the container directly affects the browning of the juice and the preservation of vitamin C; low oxygen transmission rate of metal cans, glass bottles, and aluminum foil laminated, carton on the preservation of vitamin C is better, which is the best tin cans.

3. Reduction of tin

　　Tin on the inner wall of tinplate will interact with the oxygen remaining in the container during filling to reduce the chance of oxidization of food ingredients. The reducing effect of tin has a good effect on the flavor and color of light-colored fruits and juices, so the juice cans packed in unpainted tin cans have better nutritional preservation, less browning, better acceptance of flavor and quality, and longer storage period than juice cans packed in other packaging materials.

4. Provide an effective source of iron

      Tinplate canned foods, except for a few light-colored fruits and fruit juice cans, most of them use empty cans that are painted internally to improve the corrosion resistance of the containers; due to the electrochemical effect of metals, a small amount of iron will be leached out of the painted canned foods during storage, and it exists in the form of divalent iron in the sealed canned foods, which is easily absorbed by the body, with a content of about 1 to 10 ppm. In the case of fruit and vegetable products, the raw materials themselves do not contain much iron, and the iron content of a 350 ml can with an iron content of 5 ppm can provide 1.75 mg of iron per can, which is about one-tenth of the human daily intake of 18 mg. If the above fruit and vegetable juice drink cans are rich in vitamin C, then the iron is more easily absorbed, so canned food and beverage is not a good source of iron, the significance of providing nutrition for canned food is even more far-reaching.

      Because of these properties, tinplate cans provide a closed system that is completely isolated from environmental factors except heat, avoiding deterioration of food due to light, oxygen, humidity, and not due to the aroma through the light or by environmental odors through the contamination of flavor, the stability of food storage is superior to other packaging materials, the preservation of vitamin C is the highest rate of preservation of nutrients is also the best preservation.